Determining a beam for preamble transmission

ABSTRACT

Apparatuses, methods, and systems are disclosed for determining a beam for preamble transmission. One apparatus includes a processor that determines a beam from multiple beams for preamble transmission. In response to the multiple beams including one or more beams configured with a contention-free resource, the one or more beams configured with a contention-free resource have a higher priority than other beams of the multiple beams.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 16/608,720filed on Oct. 25, 2019, which is hereby incorporated by reference in itsentirety.

FIELD

The subject matter disclosed herein relates generally to wirelesscommunications and more particularly relates to determining a beam forpreamble transmission.

BACKGROUND

The following abbreviations are herewith defined, at least some of whichare referred to within the following description: Third GenerationPartnership Project (“3GPP”), Positive-Acknowledgment (“ACK”), BinaryPhase Shift Keying (“BPSK”), Clear Channel Assessment (“CCA”), CyclicPrefix (“CP”), Cyclical Redundancy Check (“CRC”), Channel StateInformation (“CSI”), Common Search Space (“CSS”), Discrete FourierTransform Spread (“DFTS”), Downlink Control Information (“DCI”),Downlink (“DL”), Downlink Pilot Time Slot (“DwPTS”), Enhanced ClearChannel Assessment (“eCCA”), Enhanced Mobile Broadband (“eMBB”), EvolvedNode B (“eNB”), European Telecommunications Standards Institute(“ETSI”), Frame Based Equipment (“FBE”), Frequency Division Duplex(“FDD”), Frequency Division Multiple Access (“FDMA”), Guard Period(“GP”), Hybrid Automatic Repeat Request (“HARQ”), Internet-of-Things(“IoT”), Licensed Assisted Access (“LAA”), Load Based Equipment (“LBE”),Listen-Before-Talk (“LBT”), Long Term Evolution (“LTE”), Multiple Access(“MA”), Medium Access Control (“MAC”), Modulation Coding Scheme (“MCS”),Machine Type Communication (“MTC”), Multiple Input Multiple Output(“MIMO”), Multi User Shared Access (“MUSA”), Narrowband (“NB”),Negative-Acknowledgment (“NACK”) or (“NAK”), Next Generation Node B(“gNB”), Non-Orthogonal Multiple Access (“NOMA”), Orthogonal FrequencyDivision Multiplexing (“OFDM”), Primary Cell (“PCell”), PhysicalBroadcast Channel (“PBCH”), Physical Downlink Control Channel (“PDCCH”),Physical Downlink Shared Channel (“PDSCH”), Pattern Division MultipleAccess (“PDMA”), Physical Hybrid ARQ Indicator Channel (“PHICH”),Physical Random Access Channel (“PRACH”), Physical Resource Block(“PRB”), Physical Uplink Control Channel (“PUCCH”), Physical UplinkShared Channel (“PUSCH”), Quality of Service (“QoS”), Quadrature PhaseShift Keying (“QPSK”), Radio Resource Control (“RRC”), Random AccessProcedure (“RACH”), Random Access Response (“RAR”), Radio NetworkTemporary Identifier (“RNTI”), Reference Signal (“RS”), Resource SpreadMultiple Access (“RSMA”), Reference Signal Received Power (“RSRP”),Round Trip Time (“RTT”), Receive (“RX”), Sparse Code Multiple Access(“SCMA”), Scheduling Request (“SR”), Single Carrier Frequency DivisionMultiple Access (“SC-FDMA”), Secondary Cell (“SCell”), Shared Channel(“SCH”), Signal-to-Interference-Plus-Noise Ratio (“SINK”), SystemInformation Block (“SIB”), Transport Block (“TB”), Transport Block Size(“TBS”), Time-Division Duplex (“TDD”), Time Division Multiplex (“TDM”),Transmission Time Interval (“TTI”), Transmit (“TX”), Uplink ControlInformation (“UCI”), User Entity/Equipment (Mobile Terminal) (“UE”),Uplink (“UL”), Universal Mobile Telecommunications System (“UMTS”),Uplink Pilot Time Slot (“UpPTS”), Ultra-reliability and Low-latencyCommunications (“URLLC”), and Worldwide Interoperability for MicrowaveAccess (“WiMAX”). As used herein, “HARQ-ACK” may represent collectivelythe Positive Acknowledge (“ACK”) and the Negative Acknowledge (“NACK”).ACK means that a TB is correctly received while NACK (or NAK) means a TBis erroneously received.

In certain wireless communications networks, a beam may be used forpreamble transmission. In various configurations, multiple beams may beavailable for preamble transmission. In certain configurations, a beamof multiple beams available for preamble transmission may be moresuitable than other beams, but the beam may not be selected for preambletransmission.

BRIEF SUMMARY

Apparatuses for determining a beam for preamble transmission aredisclosed. Methods and systems also perform the functions of theapparatus. In one embodiment, the apparatus includes a processor thatdetermines a beam from multiple beams for preamble transmission. Incertain embodiments, in response to the multiple beams including one ormore beams configured with a contention-free resource, the one or morebeams configured with a contention-free resource have a higher prioritythan other beams of the multiple beams.

In one embodiment, the processor determines a set of suitable beams fromthe multiple beams having a signal quality greater than a predeterminedthreshold. In a further embodiment, the predetermined threshold isconfigured by a base unit. In certain embodiments, the set of beamsincludes the beam. In various embodiments, in response to the set ofsuitable beams including a single beam configured with a contention-freeresource, the processor selects the single beam from the set of suitablebeams as the beam for preamble transmission. In some embodiments, inresponse to the set of suitable beams including multiple beamsconfigured with a contention-free resource, the processor randomlyselects one beam from the multiple beams as the beam for preambletransmission. In one embodiment, in response to the set of suitablebeams including multiple beams configured with a contention-freeresource, the processor selects one beam with a best channel qualityfrom the multiple beams as the beam for preamble transmission.

In certain embodiments, in response to the set of suitable beamsincluding no beams configured with a contention-free resource, theprocessor randomly selects one beam from the set of suitable beamswithout a contention-free resource as the beam for preambletransmission. In some embodiments, in response to the set of suitablebeams including no beams configured with a contention-free resource, theprocessor selects one beam from the set of suitable beams having a bestchannel quality without contention-free resource as the beam forpreamble transmission. In various embodiments, the contention-freeresource includes time and frequency domain resource informationcorresponding to a beam and a preamble. In certain embodiments, thepreamble is enabled to be transmitted in each beam of the multiplebeams. In one embodiment, the contention-free resource is indicated byan index. In some embodiments, the apparatus includes a transmitter thattransmits the preamble transmission using the beam.

A method for determining a beam for preamble transmission, in oneembodiment, includes determining a beam from multiple beams for preambletransmission. In certain embodiments, in response to the multiple beamsincluding one or more beams configured with a contention-free resource,the one or more beams configured with a contention-free resource have ahigher priority than other beams of the multiple beams.

In one embodiment, an apparatus includes a receiver that receives apreamble transmission on a beam. In various embodiments, the beam isselected from multiple beams. In certain embodiments, in response to themultiple beams including one or more beams configured with acontention-free resource, the one or more beams configured with acontention-free resource have a higher priority than other beams of themultiple beams

In one embodiment, the beam is selected from a set of suitable beamsfrom the multiple beams having a signal quality greater than apredetermined threshold. In a further embodiment, the predeterminedthreshold is configured by the apparatus. In certain embodiments, theset of beams includes the beam. In various embodiments, in response tothe set of suitable beams including a single beam configured with acontention-free resource, the single beam from the set of suitable beamsis selected as the beam for preamble transmission. In some embodiments,in response to the set of suitable beams including multiple beamsconfigured with a contention-free resource, one beam is randomlyselected from the multiple beams as the beam for preamble transmission.In one embodiment, in response to the set of suitable beams includingmultiple beams configured with a contention-free resource, one beam witha best channel quality is selected from the multiple beams as the beamfor preamble transmission.

In certain embodiments, in response to the set of suitable beamsincluding no beams configured with a contention-free resource, one beamfrom the set of suitable beams is randomly selected without acontention-free resource as the beam for preamble transmission. In someembodiments, in response to the set of suitable beams including no beamsconfigured with a contention-free resource, one beam from the set ofsuitable beams having a best channel quality without contention-freeresource is selected as the beam for preamble transmission. In variousembodiments, the contention-free resource includes time and frequencydomain resource information corresponding to a beam and a preamble. Incertain embodiments, the preamble is enabled to be transmitted in eachbeam of the multiple beams. In one embodiment, the contention-freeresource is indicated by an index.

A method for determining a beam for preamble transmission, in oneembodiment, includes receiving a preamble transmission on a beam. Invarious embodiments, the beam is selected from multiple beams. Incertain embodiments, in response to the multiple beams including one ormore beams configured with a contention-free resource, the one or morebeams configured with a contention-free resource have a higher prioritythan other beams of the multiple beams.

BRIEF DESCRIPTION OF THE DRAWINGS

A more particular description of the embodiments briefly described abovewill be rendered by reference to specific embodiments that areillustrated in the appended drawings. Understanding that these drawingsdepict only some embodiments and are not therefore to be considered tobe limiting of scope, the embodiments will be described and explainedwith additional specificity and detail through the use of theaccompanying drawings, in which:

FIG. 1 is a schematic block diagram illustrating one embodiment of awireless communication system for determining a beam for preambletransmission;

FIG. 2 is a schematic block diagram illustrating one embodiment of anapparatus that may be used for determining a beam for preambletransmission;

FIG. 3 is a schematic block diagram illustrating one embodiment of anapparatus that may be used for receiving a beam for preambletransmission;

FIG. 4 illustrates one embodiment of communications for transmittingand/or receiving a preamble transmission;

FIG. 5 illustrates another embodiment of communications for transmittingand/or receiving a preamble transmission;

FIG. 6 illustrates one embodiment of handover communications;

FIG. 7 is a schematic flow chart diagram illustrating one embodiment ofa method for determining a beam for preamble transmission; and

FIG. 8 is a schematic flow chart diagram illustrating one embodiment ofa method for receiving a preamble transmission.

DETAILED DESCRIPTION

As will be appreciated by one skilled in the art, aspects of theembodiments may be embodied as a system, apparatus, method, or programproduct. Accordingly, embodiments may take the form of an entirelyhardware embodiment, an entirely software embodiment (includingfirmware, resident software, micro-code, etc.) or an embodimentcombining software and hardware aspects that may all generally bereferred to herein as a “circuit,” “module” or “system.” Furthermore,embodiments may take the form of a program product embodied in one ormore computer readable storage devices storing machine readable code,computer readable code, and/or program code, referred hereafter as code.The storage devices may be tangible, non-transitory, and/ornon-transmission. The storage devices may not embody signals. In acertain embodiment, the storage devices only employ signals foraccessing code.

Certain of the functional units described in this specification may belabeled as modules, in order to more particularly emphasize theirimplementation independence. For example, a module may be implemented asa hardware circuit comprising custom very-large-scale integration(“VLSI”) circuits or gate arrays, off-the-shelf semiconductors such aslogic chips, transistors, or other discrete components. A module mayalso be implemented in programmable hardware devices such as fieldprogrammable gate arrays, programmable array logic, programmable logicdevices or the like.

Modules may also be implemented in code and/or software for execution byvarious types of processors. An identified module of code may, forinstance, include one or more physical or logical blocks of executablecode which may, for instance, be organized as an object, procedure, orfunction. Nevertheless, the executables of an identified module need notbe physically located together, but may include disparate instructionsstored in different locations which, when joined logically together,include the module and achieve the stated purpose for the module.

Indeed, a module of code may be a single instruction, or manyinstructions, and may even be distributed over several different codesegments, among different programs, and across several memory devices.Similarly, operational data may be identified and illustrated hereinwithin modules, and may be embodied in any suitable form and organizedwithin any suitable type of data structure. The operational data may becollected as a single data set, or may be distributed over differentlocations including over different computer readable storage devices.Where a module or portions of a module are implemented in software, thesoftware portions are stored on one or more computer readable storagedevices.

Any combination of one or more computer readable medium may be utilized.The computer readable medium may be a computer readable storage medium.The computer readable storage medium may be a storage device storing thecode. The storage device may be, for example, but not limited to, anelectronic, magnetic, optical, electromagnetic, infrared, holographic,micromechanical, or semiconductor system, apparatus, or device, or anysuitable combination of the foregoing.

More specific examples (a non-exhaustive list) of the storage devicewould include the following: an electrical connection having one or morewires, a portable computer diskette, a hard disk, a random access memory(“RAM”), a read-only memory (“ROM”), an erasable programmable read-onlymemory (“EPROM” or Flash memory), a portable compact disc read-onlymemory (“CD-ROM”), an optical storage device, a magnetic storage device,or any suitable combination of the foregoing. In the context of thisdocument, a computer readable storage medium may be any tangible mediumthat can contain, or store a program for use by or in connection with aninstruction execution system, apparatus, or device.

Code for carrying out operations for embodiments may be any number oflines and may be written in any combination of one or more programminglanguages including an object oriented programming language such asPython, Ruby, Java, Smalltalk, C++, or the like, and conventionalprocedural programming languages, such as the “C” programming language,or the like, and/or machine languages such as assembly languages. Thecode may execute entirely on the user's computer, partly on the user'scomputer, as a stand-alone software package, partly on the user'scomputer and partly on a remote computer or entirely on the remotecomputer or server. In the latter scenario, the remote computer may beconnected to the user's computer through any type of network, includinga local area network (“LAN”) or a wide area network (“WAN”), or theconnection may be made to an external computer (for example, through theInternet using an Internet Service Provider).

Reference throughout this specification to “one embodiment,” “anembodiment,” or similar language means that a particular feature,structure, or characteristic described in connection with the embodimentis included in at least one embodiment. Thus, appearances of the phrases“in one embodiment,” “in an embodiment,” and similar language throughoutthis specification may, but do not necessarily, all refer to the sameembodiment, but mean “one or more but not all embodiments” unlessexpressly specified otherwise. The terms “including,” “comprising,”“having,” and variations thereof mean “including but not limited to,”unless expressly specified otherwise. An enumerated listing of itemsdoes not imply that any or all of the items are mutually exclusive,unless expressly specified otherwise. The terms “a,” “an,” and “the”also refer to “one or more” unless expressly specified otherwise.

Furthermore, the described features, structures, or characteristics ofthe embodiments may be combined in any suitable manner. In the followingdescription, numerous specific details are provided, such as examples ofprogramming, software modules, user selections, network transactions,database queries, database structures, hardware modules, hardwarecircuits, hardware chips, etc., to provide a thorough understanding ofembodiments. One skilled in the relevant art will recognize, however,that embodiments may be practiced without one or more of the specificdetails, or with other methods, components, materials, and so forth. Inother instances, well-known structures, materials, or operations are notshown or described in detail to avoid obscuring aspects of anembodiment.

Aspects of the embodiments are described below with reference toschematic flowchart diagrams and/or schematic block diagrams of methods,apparatuses, systems, and program products according to embodiments. Itwill be understood that each block of the schematic flowchart diagramsand/or schematic block diagrams, and combinations of blocks in theschematic flowchart diagrams and/or schematic block diagrams, can beimplemented by code. The code may be provided to a processor of ageneral purpose computer, special purpose computer, or otherprogrammable data processing apparatus to produce a machine, such thatthe instructions, which execute via the processor of the computer orother programmable data processing apparatus, create means forimplementing the functions/acts specified in the schematic flowchartdiagrams and/or schematic block diagrams block or blocks.

The code may also be stored in a storage device that can direct acomputer, other programmable data processing apparatus, or other devicesto function in a particular manner, such that the instructions stored inthe storage device produce an article of manufacture includinginstructions which implement the function/act specified in the schematicflowchart diagrams and/or schematic block diagrams block or blocks.

The code may also be loaded onto a computer, other programmable dataprocessing apparatus, or other devices to cause a series of operationalsteps to be performed on the computer, other programmable apparatus orother devices to produce a computer implemented process such that thecode which execute on the computer or other programmable apparatusprovide processes for implementing the functions/acts specified in theflowchart and/or block diagram block or blocks.

The schematic flowchart diagrams and/or schematic block diagrams in theFigures illustrate the architecture, functionality, and operation ofpossible implementations of apparatuses, systems, methods and programproducts according to various embodiments. In this regard, each block inthe schematic flowchart diagrams and/or schematic block diagrams mayrepresent a module, segment, or portion of code, which includes one ormore executable instructions of the code for implementing the specifiedlogical function(s).

It should also be noted that, in some alternative implementations, thefunctions noted in the block may occur out of the order noted in theFigures. For example, two blocks shown in succession may, in fact, beexecuted substantially concurrently, or the blocks may sometimes beexecuted in the reverse order, depending upon the functionalityinvolved. Other steps and methods may be conceived that are equivalentin function, logic, or effect to one or more blocks, or portionsthereof, of the illustrated Figures.

Although various arrow types and line types may be employed in theflowchart and/or block diagrams, they are understood not to limit thescope of the corresponding embodiments. Indeed, some arrows or otherconnectors may be used to indicate only the logical flow of the depictedembodiment. For instance, an arrow may indicate a waiting or monitoringperiod of unspecified duration between enumerated steps of the depictedembodiment. It will also be noted that each block of the block diagramsand/or flowchart diagrams, and combinations of blocks in the blockdiagrams and/or flowchart diagrams, can be implemented by specialpurpose hardware-based systems that perform the specified functions oracts, or combinations of special purpose hardware and code.

The description of elements in each figure may refer to elements ofproceeding figures. Like numbers refer to like elements in all figures,including alternate embodiments of like elements.

FIG. 1 depicts an embodiment of a wireless communication system 100 fordetermining a beam for preamble transmission. In one embodiment, thewireless communication system 100 includes remote units 102 and baseunits 104. Even though a specific number of remote units 102 and baseunits 104 are depicted in FIG. 1, one of skill in the art will recognizethat any number of remote units 102 and base units 104 may be includedin the wireless communication system 100.

In one embodiment, the remote units 102 may include computing devices,such as desktop computers, laptop computers, personal digital assistants(“PDAs”), tablet computers, smart phones, smart televisions (e.g.,televisions connected to the Internet), set-top boxes, game consoles,security systems (including security cameras), vehicle on-boardcomputers, network devices (e.g., routers, switches, modems), or thelike. In some embodiments, the remote units 102 include wearabledevices, such as smart watches, fitness bands, optical head-mounteddisplays, or the like. Moreover, the remote units 102 may be referred toas subscriber units, mobiles, mobile stations, users, terminals, mobileterminals, fixed terminals, subscriber stations, UE, user terminals, adevice, or by other terminology used in the art. The remote units 102may communicate directly with one or more of the base units 104 via ULcommunication signals.

The base units 104 may be distributed over a geographic region. Incertain embodiments, a base unit 104 may also be referred to as anaccess point, an access terminal, a base, a base station, a Node-B, aneNB, a gNB, a Home Node-B, a relay node, a device, or by any otherterminology used in the art. The base units 104 are generally part of aradio access network that includes one or more controllers communicablycoupled to one or more corresponding base units 104. The radio accessnetwork is generally communicably coupled to one or more core networks,which may be coupled to other networks, like the Internet and publicswitched telephone networks, among other networks. These and otherelements of radio access and core networks are not illustrated but arewell known generally by those having ordinary skill in the art.

In one implementation, the wireless communication system 100 iscompliant with the 3GPP protocol, wherein the base unit 104 transmitsusing an OFDM modulation scheme on the DL and the remote units 102transmit on the UL using a SC-FDMA scheme or an OFDM scheme. Moregenerally, however, the wireless communication system 100 may implementsome other open or proprietary communication protocol, for example,WiMAX, among other protocols. The present disclosure is not intended tobe limited to the implementation of any particular wirelesscommunication system architecture or protocol.

The base units 104 may serve a number of remote units 102 within aserving area, for example, a cell or a cell sector via a wirelesscommunication link. The base units 104 transmit DL communication signalsto serve the remote units 102 in the time, frequency, and/or spatialdomain.

In one embodiment, a remote unit 102 may determine a beam from multiplebeams for preamble transmission. In certain embodiments, in response tothe multiple beams including one or more beams configured with acontention-free resource, the one or more beams configured with acontention-free resource have a higher priority than other beams of themultiple beams. Accordingly, a remote unit 102 may be used fordetermining a beam for preamble transmission.

In certain embodiments, a base unit 104 may receive a preambletransmission on a beam. In various embodiments, the beam is selectedfrom multiple beams. In certain embodiments, in response to the multiplebeams including one or more beams configured with a contention-freeresource, the one or more beams configured with a contention-freeresource have a higher priority than other beams of the multiple beams.Accordingly, a base unit 104 may be used for receiving a preambletransmission.

FIG. 2 depicts one embodiment of an apparatus 200 that may be used fordetermining a beam for preamble transmission. The apparatus 200 includesone embodiment of the remote unit 102. Furthermore, the remote unit 102may include a processor 202, a memory 204, an input device 206, adisplay 208, a transmitter 210, and a receiver 212. In some embodiments,the input device 206 and the display 208 are combined into a singledevice, such as a touchscreen. In certain embodiments, the remote unit102 may not include any input device 206 and/or display 208. In variousembodiments, the remote unit 102 may include one or more of theprocessor 202, the memory 204, the transmitter 210, and the receiver212, and may not include the input device 206 and/or the display 208.

The processor 202, in one embodiment, may include any known controllercapable of executing computer-readable instructions and/or capable ofperforming logical operations. For example, the processor 202 may be amicrocontroller, a microprocessor, a central processing unit (“CPU”), agraphics processing unit (“GPU”), an auxiliary processing unit, a fieldprogrammable gate array (“FPGA”), or similar programmable controller. Insome embodiments, the processor 202 executes instructions stored in thememory 204 to perform the methods and routines described herein. Invarious embodiments, the processor 202 determines a beam from multiplebeams for preamble transmission. In certain embodiments, in response tothe multiple beams including one or more beams configured with acontention-free resource, the one or more beams configured with acontention-free resource have a higher priority than other beams of themultiple beams. The processor 202 is communicatively coupled to thememory 204, the input device 206, the display 208, the transmitter 210,and the receiver 212.

The memory 204, in one embodiment, is a computer readable storagemedium. In some embodiments, the memory 204 includes volatile computerstorage media. For example, the memory 204 may include a RAM, includingdynamic RAM (“DRAM”), synchronous dynamic RAM (“SDRAM”), and/or staticRAM (“SRAM”). In some embodiments, the memory 204 includes non-volatilecomputer storage media. For example, the memory 204 may include a harddisk drive, a flash memory, or any other suitable non-volatile computerstorage device. In some embodiments, the memory 204 includes bothvolatile and non-volatile computer storage media. In some embodiments,the memory 204 stores data relating to beam selection. In someembodiments, the memory 204 also stores program code and related data,such as an operating system or other controller algorithms operating onthe remote unit 102.

The input device 206, in one embodiment, may include any known computerinput device including a touch panel, a button, a keyboard, a stylus, amicrophone, or the like. In some embodiments, the input device 206 maybe integrated with the display 208, for example, as a touchscreen orsimilar touch-sensitive display. In some embodiments, the input device206 includes a touchscreen such that text may be input using a virtualkeyboard displayed on the touchscreen and/or by handwriting on thetouchscreen. In some embodiments, the input device 206 includes two ormore different devices, such as a keyboard and a touch panel.

The display 208, in one embodiment, may include any known electronicallycontrollable display or display device. The display 208 may be designedto output visual, audible, and/or haptic signals. In some embodiments,the display 208 includes an electronic display capable of outputtingvisual data to a user. For example, the display 208 may include, but isnot limited to, an LCD display, an LED display, an OLED display, aprojector, or similar display device capable of outputting images, text,or the like to a user. As another, non-limiting, example, the display208 may include a wearable display such as a smart watch, smart glasses,a heads-up display, or the like. Further, the display 208 may be acomponent of a smart phone, a personal digital assistant, a television,a table computer, a notebook (laptop) computer, a personal computer, avehicle dashboard, or the like.

In certain embodiments, the display 208 includes one or more speakersfor producing sound. For example, the display 208 may produce an audiblealert or notification (e.g., a beep or chime). In some embodiments, thedisplay 208 includes one or more haptic devices for producingvibrations, motion, or other haptic feedback. In some embodiments, allor portions of the display 208 may be integrated with the input device206. For example, the input device 206 and display 208 may form atouchscreen or similar touch-sensitive display. In other embodiments,the display 208 may be located near the input device 206.

The transmitter 210 is used to provide UL communication signals to thebase unit 104 and the receiver 212 is used to receive DL communicationsignals from the base unit 104. In certain embodiments, the transmitter210 may be used to transmit a preamble. Although only one transmitter210 and one receiver 212 are illustrated, the remote unit 102 may haveany suitable number of transmitters 210 and receivers 212. Thetransmitter 210 and the receiver 212 may be any suitable type oftransmitters and receivers. In one embodiment, the transmitter 210 andthe receiver 212 may be part of a transceiver.

FIG. 3 depicts one embodiment of an apparatus 300 that may be used forreceiving a beam for preamble transmission. The apparatus 300 includesone embodiment of the base unit 104. Furthermore, the base unit 104 mayinclude a processor 302, a memory 304, an input device 306, a display308, a transmitter 310, and a receiver 312. As may be appreciated, theprocessor 302, the memory 304, the input device 306, the display 308,the transmitter 310, and the receiver 312 may be substantially similarto the processor 202, the memory 204, the input device 206, the display208, the transmitter 210, and the receiver 212 of the remote unit 102,respectively.

In various embodiments, the receiver 312 may be used to receive apreamble transmission on a beam. In various embodiments, the beam isselected from multiple beams. In certain embodiments, in response to themultiple beams including one or more beams configured with acontention-free resource, the one or more beams configured with acontention-free resource have a higher priority than other beams of themultiple beams. Although only one transmitter 310 and one receiver 312are illustrated, the base unit 104 may have any suitable number oftransmitters 310 and receivers 312. The transmitter 310 and the receiver312 may be any suitable type of transmitters and receivers. In oneembodiment, the transmitter 310 and the receiver 312 may be part of atransceiver.

FIG. 4 illustrates one embodiment of communications 400 for transmittingand/or receiving a preamble transmission. Specifically, communicationsbetween a UE 402 (e.g., remote unit 102) and a gNB 404 (e.g., base unit104) are illustrated. The communications 400 may illustrate a contentionbased random access procedure.

Moreover, the communications 400 include a first communication 406 inwhich the UE 402 transmits a random access preamble (e.g., preambletransmission) on RACH in uplink to the gNB 404. The communications 400include a second communication 408 in which the gNB 404 transmits arandom access response generated by MAC on DL-SCH to the UE 402.Further, the communications 400 include a third communication 410 inwhich the UE 402 transmits a scheduled UL transmission on UL-SCH to thegNB 404. In addition, the communications 400 include a fourthcommunication 412 in which the gNB 404 transmits a contention resolutionon DL to the UE 402.

FIG. 5 illustrates another embodiment of communications 500 fortransmitting and/or receiving a preamble transmission. Specifically,communications between a UE 502 (e.g., remote unit 102) and a gNB 504(e.g., base unit 104) are illustrated. The communications 500 mayillustrate a contention free based random access procedure.

Moreover, the communications 500 include a first communication 506 inwhich the gNB 504 transmits a random access preamble assignment viadedicated signaling in DL to the UE 502. The communications 500 includea second communication 508 in which the UE 502 transmits a random accesspreamble (e.g., preamble transmission) on RACH in uplink to the gNB 504.The communications 500 include a third communication 510 in which thegNB 504 transmits a random access response on DL-SCH to the UE 502.

FIG. 6 illustrates one embodiment of handover communications 600.Specifically, communications between a UE 602 (e.g., remote unit 102), asource gNB 604 (e.g., base unit 104), and a target gNB 606 (e.g., baseunit 104) are illustrated.

Moreover, the communications 600 include a first communication 608 inwhich the source gNB 604 transmits a handover request to the target gNB606. The target gNB 606 performs admission control 610. Thecommunications 600 include a second communication 612 in which thetarget gNB 606 transmits a handover acknowledgement to the source gNB604. The communications 600 include a third communication 614 in whichthe source gNB 604 transmits a handover command to the UE 602. The UE602 switches 616 to the new cell. Further, the communications 600include a fourth communication 618 in which the UE 602 transmits ahandover complete message to the target gNB 606.

In certain embodiments, such as in conjunction with and/or in additionto the communications described in FIGS. 4 through 6, a remote unit 102may be initialized for random access, select a beam to be used fortransmission, transmit a preamble using the selected beam, and/orreceiving a random access response.

Initialization of a remote unit 102 may be performed in various ways. Incertain embodiments, contention-free resources may include time andfrequency domain RACH resources associated to a beam and one dedicatedpreamble. In some embodiments, contention-free resources may beconfigured by a base unit 104. In various embodiments, a base unit 104may configure multiple contention-free resource for beams. In oneembodiment, a dedicated preamble may be transmitted in all beams withinone cell. In certain embodiments, contention-free resources for randomaccess may be provided by DCI or RRC signaling. In some embodiments, abeam may be identified by a beam identification (“ID”), synchronizationsignal (“SS”) block, and/or a time index.

A beam of a remote unit 102 may be selected, in certain embodiments, bythe remote unit 102 determining a set of suitable beams of which thesignal quality is better than a threshold configured by a base unit 104.As used herein, “suitable beams” may refer to beams that have a signalquality greater and/or better than a threshold signal quality. In someembodiments, if one beam of a remote unit 102 is configured with acontention-free resource and is available in a set of suitable beams,the remote unit 102 may select this beam with a contention-free resourceas a highest priority beam. In various embodiments, if there aremultiple suitable beams of a remote unit 102 with a contention-freeresource in a set of suitable beams, the remote unit 102 may randomlyselect one of the beams and/or the remote unit 102 may select a beamwith the best channel quality, such as based on RSRP. In one embodiment,if there are no beams of a remote unit 102 configured with acontention-free resource in a set of suitable beams, the remote unit 102may randomly select one of the set of suitable beams and/or the remoteunit 102 may select a beam with a best channel quality, such as based onRSRP.

In various embodiments, if a contention-free resource is provided to aremote unit 102, the remote unit 102 may transmit a dedicated preamblein a configured contention-free RACH resource. In certain embodiments,if there is no contention-free resource provided to a remote unit 102,the remote unit 102 may select one preamble and transmit the selectedpreamble in a selected RACH resource.

In some embodiments, if a random access response contains a randomaccess preamble (“RAP”) identifier corresponding to a transmitted randomaccess preamble and if the transmitted preamble is dedicated, a remoteunit 102 may consider a random access procedure successful. In certainembodiments, if a transmitted preamble is from random selection, aremote unit 102 may consider any random access response receptionsuccessful. In some embodiments, a remote unit 102 may transmit amessage including a remote unit 102 ID to a base unit 104. In suchembodiments, after the base unit 104 receives this message, the baseunit 102 may send a response to the remote unit 102. Further, if theremote unit 102 receives the response including a transmitted remoteunit 102 ID, the remote unit 102 may consider this random accessprocedure successful. In certain embodiments, a remote unit 102 ID mayinclude a system architecture evolution temporary mobile subscriberidentity (“S-TMSI”) and/or a random number.

FIG. 7 is a schematic flow chart diagram illustrating one embodiment ofa method 700 for determining a beam for preamble transmission. In someembodiments, the method 700 is performed by an apparatus, such as theremote unit 102. In certain embodiments, the method 700 may be performedby a processor executing program code, for example, a microcontroller, amicroprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, orthe like.

The method 700 may include determining 702 a beam from multiple beamsfor preamble transmission. In certain embodiments, in response to themultiple beams including one or more beams configured with acontention-free resource, the one or more beams configured with acontention-free resource have a higher priority than other beams of themultiple beams.

In one embodiment, the method 700 includes determining a set of suitablebeams from the multiple beams having a signal quality greater than apredetermined threshold. In a further embodiment, the predeterminedthreshold is configured by a base unit. In certain embodiments, the setof beams includes the beam. In various embodiments, in response to theset of suitable beams including a single beam configured with acontention-free resource, the method 700 includes selecting the singlebeam from the set of suitable beams as the beam for preambletransmission. In some embodiments, in response to the set of suitablebeams including multiple beams configured with a contention-freeresource, the method 700 includes randomly selecting one beam from themultiple beams as the beam for preamble transmission. In one embodiment,in response to the set of suitable beams including multiple beamsconfigured with a contention-free resource, the method 700 includesselecting one beam with a best channel quality from the multiple beamsas the beam for preamble transmission.

In certain embodiments, in response to the set of suitable beamsincluding no beams configured with a contention-free resource, themethod 700 includes randomly selecting one beam from the set of suitablebeams without a contention-free resource as the beam for preambletransmission. In some embodiments, in response to the set of suitablebeams including no beams configured with a contention-free resource, themethod 700 includes selecting one beam from the set of suitable beamshaving a best channel quality without contention-free resource as thebeam for preamble transmission. In various embodiments, thecontention-free resource includes time and frequency domain resourceinformation corresponding to a beam and a preamble. In certainembodiments, the preamble is enabled to be transmitted in each beam ofthe multiple beams. In one embodiment, the contention-free resource isindicated by an index. In some embodiments, the method 700 includestransmitting the preamble transmission using the beam.

FIG. 8 is a schematic flow chart diagram illustrating one embodiment ofa method 800 for receiving a preamble transmission. In some embodiments,the method 800 is performed by an apparatus, such as the base unit 104.In certain embodiments, the method 800 may be performed by a processorexecuting program code, for example, a microcontroller, amicroprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, orthe like.

The method 800 may include receiving 802 a preamble transmission on abeam. In various embodiments, the beam is selected from multiple beams.In certain embodiments, in response to the multiple beams including oneor more beams configured with a contention-free resource, the one ormore beams configured with a contention-free resource have a higherpriority than other beams of the multiple beams.

In one embodiment, the beam is selected from a set of suitable beamsfrom the multiple beams having a signal quality greater than apredetermined threshold. In a further embodiment, the predeterminedthreshold is configured by an apparatus. In certain embodiments, the setof beams includes the beam. In various embodiments, in response to theset of suitable beams including a single beam configured with acontention-free resource, the single beam from the set of suitable beamsis selected as the beam for preamble transmission. In some embodiments,in response to the set of suitable beams including multiple beamsconfigured with a contention-free resource, one beam is randomlyselected from the multiple beams as the beam for preamble transmission.In one embodiment, in response to the set of suitable beams includingmultiple beams configured with a contention-free resource, one beam witha best channel quality is selected from the multiple beams as the beamfor preamble transmission.

In certain embodiments, in response to the set of suitable beamsincluding no beams configured with a contention-free resource, one beamfrom the set of suitable beams is randomly selected without acontention-free resource as the beam for preamble transmission. In someembodiments, in response to the set of suitable beams including no beamsconfigured with a contention-free resource, one beam from the set ofsuitable beams having a best channel quality without contention-freeresource is selected as the beam for preamble transmission. In variousembodiments, the contention-free resource includes time and frequencydomain resource information corresponding to a beam and a preamble. Incertain embodiments, the preamble is enabled to be transmitted in eachbeam of the multiple beams. In one embodiment, the contention-freeresource is indicated by an index.

Embodiments may be practiced in other specific forms. The describedembodiments are to be considered in all respects only as illustrativeand not restrictive. The scope of the invention is, therefore, indicatedby the appended claims rather than by the foregoing description. Allchanges which come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

1. An apparatus comprising a base unit, the apparatus furthercomprising: a receiver that receives a preamble transmission on a beam,wherein the beam is selected by a user equipment from a plurality ofbeams, and, in response to the plurality of beams comprising one or morebeams that are configured with a contention-free resource, the one ormore beams that are configured with a contention-free resource have ahigher priority than other beams of the plurality of beams, wherein theuser equipment: determines a set of suitable beams from the plurality ofbeams having a signal quality greater than a predetermined threshold; inresponse to the set of suitable beams comprising a single beamconfigured with the contention-free resource, selects the single beamfrom the set of suitable beams as the beam for preamble transmission; inresponse to the set of suitable beams comprising multiple beamsconfigured with the contention-free resource, selects one beam from themultiple beams as the beam for preamble transmission; and in response tothe set of suitable beams comprising no beams configured with thecontention-free resource, selects one beam from the set of suitablebeams without a contention-free resource as the beam for preambletransmission; and a transmitter that transmits a response to thereception of the preamble transmission.
 2. The apparatus of claim 1,wherein the transmitter transmits the response to the preambletransmission using a medium access control transmission.
 3. Theapparatus of claim 1, wherein the transmitter transmits the response tothe preamble transmission using a downlink shared channel transmission.4. The apparatus of claim 1, wherein the receiver receives an uplinktransmission from the user equipment.
 5. The apparatus of claim 4,wherein the uplink transmission is a shared channel uplink transmission.6. The apparatus of claim 4, wherein the transmitter transmits acontention resolution message to the user equipment in response to thereceiver receiving the uplink transmission.
 7. A method of a base unit,the method comprising: receiving a preamble transmission on a beam,wherein the beam is selected by a user equipment from a plurality ofbeams, and, in response to the plurality of beams comprising one or morebeams that are configured with a contention-free resource, the one ormore beams that are configured with a contention-free resource have ahigher priority than other beams of the plurality of beams, wherein theuser equipment: determines a set of suitable beams from the plurality ofbeams having a signal quality greater than a predetermined threshold; inresponse to the set of suitable beams comprising a single beamconfigured with the contention-free resource, selects the single beamfrom the set of suitable beams as the beam for preamble transmission; inresponse to the set of suitable beams comprising multiple beamsconfigured with the contention-free resource, selects one beam from themultiple beams as the beam for preamble transmission; and in response tothe set of suitable beams comprising no beams configured with thecontention-free resource, selects one beam from the set of suitablebeams without a contention-free resource as the beam for preambletransmission; and transmitting a response to the reception of thepreamble transmission.
 8. The method of claim 7, further comprisingtransmitting the response to the preamble transmission using a mediumaccess control transmission.
 9. The method of claim 7, furthercomprising transmitting the response to the preamble transmission usinga downlink shared channel transmission.
 10. The method of claim 7,further comprising receiving an uplink transmission from the userequipment.
 11. The method of claim 10, wherein the uplink transmissionis a shared channel uplink transmission.
 12. The method of claim 10,further comprising transmitting a contention resolution message to theuser equipment in response to receiving the uplink transmission.
 13. Anapparatus comprising a user equipment, the apparatus further comprising:a processor that: determines a beam from a plurality of beams forpreamble transmission, wherein, in response to the plurality of beamscomprising one or more beams that are configured with a contention-freeresource, the one or more beams that are configured with acontention-free resource have a higher priority than other beams of theplurality of beams; and determines a set of suitable beams from theplurality of beams having a signal quality greater than a predeterminedthreshold; wherein: in response to the set of suitable beams comprisinga single beam configured with the contention-free resource, theprocessor selects the single beam from the set of suitable beams as thebeam for preamble transmission; in response to the set of suitable beamscomprising multiple beams configured with the contention-free resource,the processor selects one beam from the multiple beams as the beam forpreamble transmission; and in response to the set of suitable beamscomprising no beams configured with the contention-free resource, theprocessor selects one beam from the set of suitable beams without acontention-free resource as the beam for preamble transmission.
 14. Theapparatus of claim 13, wherein the predetermined threshold is configuredby a base unit.
 15. The apparatus of claim 13, wherein the set ofsuitable beams comprises the beam.
 16. The apparatus of claim 13,wherein, in response to the set of suitable beams comprising multiplebeams configured with the contention-free resource, the processorselects one beam with a best channel quality from the multiple beams asthe beam for preamble transmission.
 17. The apparatus of claim 13,wherein, in response to the set of suitable beams comprising no beamsconfigured with the contention-free resource, the processor selects onebeam from the set of suitable beams having a best channel qualitywithout contention-free resource as the beam for preamble transmission.18. The apparatus of claim 13, wherein the contention-free resourcecomprises time and frequency domain resource information correspondingto a beam and a preamble.
 19. The apparatus of claim 18, wherein thepreamble is enabled to be transmitted using any beam of the plurality ofbeams.
 20. The apparatus of claim 18, wherein the contention-freeresource is indicated by an index.